(a) Technical Field
The present disclosure relates to a liquid crystal display and a manufacturing method thereof.
(b) Discussion of the Related Art
A liquid crystal display (LCD) is one of the most widely used flat panel displays. An LCD includes two display panels provided with field-generating electrodes such as pixel electrodes and a common electrode, and a liquid crystal (LC) layer interposed therebetween. The LCD displays images by applying voltages to the field-generating electrodes to generate an electric field in the LC layer, which determines orientations of LC molecules in the LC layer to adjust polarization of incident light.
The two display panels of the LCD are combined together by a sealant which is formed on each circumferential edge of the display panels to seal a liquid crystal material therein, and the two display panels are supported by spacers provided therebetween to sustain a cell gap therebetween.
The spacers can be categorized as spherical bead spacers formed in an irregular pattern and column spacers formed in a uniform pattern.
The column spacers are formed in a desired pattern corresponding to portions inside pixels where light is not transmitted, namely, for example, at a channel portion, a gate line, a storage electrode line, or a light blocking member, after coating a photosensitive film on a color filter array panel and then exposing and developing it.
The bead spacers are formed by spreading them irregularly before the two display panels are coupled together. However, when the bead spacers are formed in this way, the bead spacers may act as foreign particles causing light leakage which deteriorates the contrast ratio, or some bead spacers may move slightly, damaging an alignment layer.
The two display panels of an LCD are combined by fixing them to face each other using an unhardened sealant and hardening the unhardened sealant using light or heat. The liquid crystal material may be contaminated by contacting the unhardened sealant during an assembly process for combining the two display panels, causing defective alignment of the liquid crystal. Accordingly, a dam may be formed at the circumference of one display panel and the liquid crystal material may be enclosed by the dam to prevent the liquid crystal material from contacting the unhardened sealant.
However, the dam may have a non-uniform height, allowing the liquid crystal material to move to the unhardened sealant through low portions of the dam. Also, additional processes for manufacturing the dam cause manufacturing time and cost of an LCD to increase.